Radio frequency identification (RFID) technology enables automatic identification of unique items by using radio frequency (RF) signals. A typical RFID system includes a tag, a reader, an antenna, and a host system. The reader gathers information about an object by communicating through the antenna with the tag attached to the object. The host system then processes the data collected by the reader to obtain information related to the tagged object.
RFID systems often have reading or interrogation fields having a wide range which can present a problem of differentiating an individual product or a case that needs to be detected among other tagged items. RFID portals are limited in that they distinguish only the items passing through the portal, for example, a duck door, while reading every other tag in the field. On the other hand, in RFID systems that have shorter or more directed read ranges, such as high frequency (HF) systems or handheld devices, the antenna has to be in very close proximity and almost aimed at a particular tag in order to read it. Having to aim the RFID device undermines at least some of the benefits of using an RFID system. Moreover, the data collected still needs to be confirmed due to the high probability of reading an unwanted tag. These aimed devices can also occupy the user's hands, making handling of items more difficult or time consuming.
Current wearable RFID systems have antenna designs that severely limit their interrogation or read ranges. The limited interrogation or read ranges, sometimes only one to two inches, require that these systems still be “aimed” at the desired tag to ensure interrogation. This aiming can disrupt a worker's normal handling of tagged objects and decrease processing accuracy or efficiency. Initial studies show that aiming can significantly increase the processing time required when handling items.
Accordingly, there is a need for a method and system that allows interrogation of RFID tagged items when the items are handled individually while among other items, such as during typical warehouse or retail store activity of preparing an order, breaking up a pallet or a case, or associating cases to pallets, without disrupting the handling process. Specifically, there is a need for a wearable RFID system with an increased interrogation and read range that does not lose the sought after RFID tag among others within the interrogation field.